DE102017222941A1 - High voltage circuit breaker and method for electromagnetically shielding a vacuum interrupter in an insulator - Google Patents

Abstract

The invention relates to a high voltage circuit breaker (1) and a method for electromagnetic shielding at least one vacuum interrupter (2) in an insulator (3) of a high voltage circuit breaker (1). The high-voltage circuit breaker (1) comprises at least one vacuum interrupter (2), which is arranged in an insulator (3) and at least one shielding ring (4), wherein the at least one shielding ring (4) in a sectional plane along a rotation axis (5) of the Abschirmrings (4) has two cross sections (6) deviating from a circular cross section.

Description

The invention relates to a high voltage circuit breaker and a method for electromagnetic shielding at least one vacuum interrupter in an insulator of a high voltage circuit breaker. The high-voltage circuit breaker comprises at least one vacuum interrupter, which is arranged in an insulator and which has at least one shielding ring.

High voltage circuit breakers are designed to switch voltages in the range of up to 1200 kV voltage and in the range of up to several thousand amperes of current. In this case, switching gases such. B. SF _{6 is} used, which are harmful to the environment and / or contain toxic components. A long-term stable, gas-tight insulation of the high-voltage circuit breaker, which reliably prevents the escape of gases, is expensive and increases the cost of maintenance. Switch with alternative switching gases, such. As clean air, ie dry, purified air, with the same design and at the same maximum switching voltages or currents to be switched, larger in dimensions to ensure a secure electrical insulation between the electrically conductive components, which increases the cost. The use of vacuum interrupters in high voltage circuit breakers, in conjunction with Clean Air as insulating, is an alternative to z. B. gas-insulated switches with nominal and arcing contacts, comprising switching gases such. B. SF ₆ .

The vacuum interrupters are arranged in an outer insulator, which z. B. columnar, is formed with circular circumferential ribs on the outer periphery to increase the electrical insulation along the outer surface in the direction of the longitudinal axis. The insulator is one or more parts, in particular hollow cylindrical, and z. As ceramic, silicone and / or a composite material. The insulator is arranged upright in the operation of the high voltage circuit breaker, z. B. on a support frame or on a support with foundation. One or more vacuum interrupters are z. B. along the longitudinal axis of the insulator, in particular arranged coaxially with the longitudinal axis of the insulator and fixed mechanically fixed in the insulator. The high-voltage circuit breaker may comprise more than one vacuum interrupter connected in series and / or in parallel, wherein for the sake of simplicity it is further assumed that a vacuum interrupter is used.

The vacuum interrupter is mechanically stable and electrically conductively arranged and connected between at least two external electrical terminals in the interior of the insulator, wherein the electrical connections z. B. in the form of connecting lugs for connecting high voltage power lines, generators and / or power consumers are formed. The construction of a vacuum interrupter for high-voltage circuit breaker is z. B. from the EP 0 102 317 A2 known. The vacuum interrupter comprises a housing in the form of a circular, straight cylinder, which is evacuated inside. The housing is constructed of two equal, straight cylindrical halves made of ceramic or ceramic parts, which are joined together via a metal cylinder or via a metal part with transition pieces in the middle of the housing. The transition pieces are designed in the housing as shielding electrodes or shielding.

The vacuum interrupter comprises at least one electrical contact with a fixed and a movable contact piece for switching. Alternatively, a plurality of movable contact pieces may be comprised by the at least one electrical contact, with or without a fixed contact piece. In the following, it is assumed for the sake of simplicity of a vacuum interrupter with a fixed and a movable contact piece.

The contacts are plate-shaped in the vacuum interrupter and enclosed by vacuum. To the outside, the contact pieces are bolt-shaped and each electrically connected to an external electrical connection z. B. connected in the form of a terminal lug of the high voltage circuit breaker. The movable contact piece is guided in a vacuum-tight manner via a bellows in the vacuum interrupter and stored.

When switching on, the movable contact piece is moved toward the fixed contact piece until there is mechanical and electrical contact between the contact pieces. When switching off the movable contact piece is moved away from the fixed contact piece until the electrical contact between the contact pieces is interrupted and there is a sufficient distance to avoid electrical flashovers with voltage applied. At high voltages, eg. B. in the range of 145 kV, large distances between the contact pieces are necessary. The vacuum interrupter is designed to be long enough to ensure sufficient space inside. The straight cylindrical halves of ceramic or ceramic parts of the housing of the vacuum interrupter are made up of several parts, which are joined together via metal parts with transition pieces. The transition pieces are each designed in the housing as shielding electrodes or shielding. Connecting ceramic parts of the housing via metal parts, which z. B. of copper and / or steel, z. B. by soldering.

Electromagnetic fields around the contacts are shielded in the vacuum interrupter by the shield electrodes. Along the outer circumference of the vacuum interrupter, the metal parts with transition pieces are each formed as a circular ring, and serve as a shield for electromagnetic fields. The annular shields along the outer circumference of the vacuum interrupter are disposed in a plane perpendicular to a longitudinal axis of the vacuum interrupter, and have two circular cross-sections in a section along the longitudinal axis. In order to avoid electrical flashovers between the annular shields of the vacuum interrupter via an inner wall of the outer insulator of the high voltage circuit breaker, the Abschirmringe the vacuum interrupter are spaced from the inner wall of the insulator.

In particular, in vacuum interrupters with cylindrical parts of the housing, which have the same diameter, the outer circumference of the vacuum interrupter is determined by the outer circumference of the shielding rings of the vacuum interrupter. The distance d the shielding rings of the vacuum interrupter of the inner wall of the insulator in conjunction with the ring diameter of the shielding rings determines the circumference of the insulator of the high voltage circuit breaker. A large amount is associated with high production costs and high material costs of the insulator.

Object of the present invention is to provide a high voltage circuit breaker and a method for electromagnetic shielding at least one vacuum interrupter in an insulator of a high voltage circuit breaker, which allow a reduced compared to the prior art circumference of the insulator of the high voltage circuit breaker, allow lower manufacturing costs and a lower material cost for the insulator enable.

The stated object is achieved by a high-voltage circuit breaker with the features of claim 1 and / or by a method for electromagnetic shielding at least one vacuum interrupter in an insulator of a high voltage circuit breaker, in particular a high-voltage circuit breaker described above, according to claim 11. Advantageous embodiments of the high-voltage circuit breaker according to the invention and / or the method according to the invention for the electromagnetic shielding of at least one vacuum interrupter in an insulator of a high-voltage circuit breaker, in particular a high-voltage circuit breaker described above, are specified in the subclaims. In this case, objects of the main claims with each other and with features of subclaims and features of the dependent claims can be combined with each other.

An inventive high-voltage circuit breaker comprises at least one vacuum interrupter, which is arranged in an insulator and comprises at least one shielding ring. The at least one shielding ring has, in a sectional plane along an axis of rotation of the shielding ring, two cross sections deviating from a circular cross section. In this context, the axis of rotation of the shielding ring that is perpendicular to the plane of the ring is designated by the center point of the circular ring.

Cross-section deviating from a circular cross-section enables good shielding of the vacuum interrupter, a smaller outer circumference of the vacuum interrupter compared to vacuum interrupters with circular cross-section shielding rings, and thus a smaller circumference of the high voltage circuit breaker insulator coupled with lower manufacturing costs and less insulator material.

The at least one shielding ring can have two elliptical and / or oval, raceway-like cross-sections and / or rectangular cross-sections with rounded corners in the sectional plane of the axis of rotation. Such cross-sections have the same shielding a smaller diameter in one direction than circular cross-sections with the advantages described above.

The at least one vacuum interrupter can be circular-cylindrical and the insulator can be hollow-cylindrical, with a circular base, wherein the at least one vacuum interrupter can be arranged coaxially in the insulator. The axis of rotation of the at least one shielding ring may be coaxial with the longitudinal axis of the at least one vacuum interrupter. As a result, shielding rings of the vacuum interrupter along the circumference have the same everywhere, in particular minimum distance to the inner wall of the insulator. The insulator may be formed with a minimum circumference, with the advantages described above.

The at least one shielding ring may be arranged circumferentially around the outer circumference of the at least one vacuum interrupter, in particular mechanically stably connected to the at least one vacuum interrupter. As a result, changes in position of the at least one shielding ring during operation of the high-voltage circuit breaker z. B. avoided by mechanical shocks and electrical flashovers are prevented by changing distances of the shielding rings.

The cross sections of the at least one shielding ring can be flattened in the sectional plane of the axis of rotation of the at least one shielding ring in the direction of the at least one vacuum interrupter and / or in the direction of the inner wall of the insulator. With the same shielding effect, such cross-sections have a smaller diameter in the direction of the vacuum interrupter and / or the inner wall of the insulator than circular cross-sections, with the advantages described above.

Two, four or at least six shielding rings may be included. In particular regular arrangement of the Abschirmringe along the longitudinal axis of the vacuum interrupter on the outer circumference of the vacuum interrupter, a good electromagnetic shielding of the vacuum interrupter tube can be achieved in particular to the outside.

The at least one shielding ring can be mechanically and / or electrically connected to at least one shielding electrode in the interior of the at least one vacuum interrupter. Thereby, a good electromagnetic shielding of the vacuum interrupter, in particular to the outside, can be achieved, and the shielding electrode in the interior of the at least one vacuum interrupter and the at least one shielding ring can be mechanically stably fixed.

The at least one shielding ring can be formed from a conductive material, in particular a metal, in particular copper and / or steel, or a conductive plastic, or plastic with conductive particles, in particular silicone with soot particles. Copper and steel have a good electrical conductivity and allow a good shielding effect or damping of electromagnetic fields at a given shape. The same applies to conductive plastics, and / or plastics with conductive particles, such as. B. silicone with soot particles. In particular, damped, induced currents in the shielding ring and / or influencing the field line course of an electromagnetic field can enable a good shielding effect.

The at least one shielding ring can have a minimum and / or maximum distance d to the inner wall of the insulator in the range of millimeters to a few centimeters. Such a distance d prevents flashovers between Abschirmringen on the inner wall of the insulator, in particular when filling the insulator with an insulating gas such. B. Clean Air.

A method according to the invention for the electromagnetic shielding of at least one vacuum interrupter in an insulator of a high-voltage circuit breaker, in particular in a high-voltage circuit breaker described above, comprises an electromagnetic shielding of the at least one vacuum interrupter by at least one shielding ring whose two cross-sections are in the sectional plane of the axis of rotation adjacent to the at least one vacuum interrupter and / or or flattened adjacent to the insulator compared to the cross section in the direction parallel to the axis of rotation.

The advantages of the inventive method for electromagnetic shielding at least one vacuum interrupter in an insulator of a high voltage circuit breaker, in particular a previously described high voltage circuit breaker according to claim 11 are analogous to the advantages of the high voltage circuit breaker according to the invention according to claim 1 and vice versa.

In the following, embodiments of the invention are schematically illustrated in FIGS 1 to 4 shown and described in more detail below.

• 1 schematisch in Schnittansicht einen erfindungsgemäßen Hochspannungsleistungsschalter 1 von einer Seite betrachtet, mit Abschirmringen 4 der Vakuumschaltröhre 2 mit von einem kreisförmigen Querschnitt abweichenden Querschnitten 6, und
• 2 schematisch in Schnittansicht einen vergrößerten Ausschnitt eines Abschirmrings 4 der 1 mit elliptischen Querschnitten 6, und
• 3 schematisch in Schnittansicht einen vergrößerten Ausschnitt eines Abschirmrings 4 der 1 mit ovalen, rennbahnartigen Querschnitten 6, und
• 4 schematisch in Schnittansicht einen vergrößerten Ausschnitt eines Abschirmrings 4 der 1 mit rechteckigen Querschnitten 6 mit abgerundeten Ecken.

It shows the

• 1 schematically in sectional view a high-voltage circuit breaker according to the invention 1 viewed from one side, with shielding rings 4 the vacuum interrupter 2 with cross sections deviating from a circular cross section 6 , and
• 2 schematically in sectional view an enlarged section of a shield 4 the 1 with elliptical cross sections 6 , and
• 3 schematically in sectional view an enlarged section of a shield 4 the 1 with oval, racetrack-like cross sections 6 , and
• 4 schematically in sectional view an enlarged section of a shield 4 the 1 with rectangular cross sections 6 with rounded corners.

In 1 is a schematic sectional view of a section of a high-voltage circuit breaker according to the invention 1 viewed from one side. The high voltage circuit breaker 1 includes a vacuum interrupter 2 which is in an isolator 3 is arranged. The insulator 3 is z. B. filled with clean air as insulating gas and the vacuum interrupter 2 is with the longitudinal axis 5 coaxial to the longitudinal axis 5 of the insulator 3 , spaced from the insulator 3 arranged. The minimum distance d between vacuum tube 2 and inner wall 7 of the insulator is z. In the range of millimeters or centimeters.

The high voltage circuit breaker 1 is constructed analog high-voltage circuit breakers, which include nominal and arcing contact pieces and z. B. are filled with SF ₆ , only that instead of nominal and arcing contact pieces a vacuum interrupter 2 is included, and as insulating gas z. B. Clean Air is used. The insulator 3 is z. As ceramic, silicone, and / or an electrically insulating composite material. The insulator 3 is columnar, circular cylindrical, hollow, with annular ridges along the outer periphery, with the advantages described above. The base and top surfaces of the columnar insulator 3 are hermetically sealed and each with external electrical connections of the high voltage circuit breaker 1 provided, which is not shown in the figures for simplicity.

The vacuum interrupter 2 is in the area of the base and top surface, in particular via brackets, mechanically in the insulator 3 spatially fixed and electrically connected to the outer terminals of the high voltage circuit breaker 1 connected, which is also not shown in the figures for the sake of simplicity. A drive, for. As a spring-loaded drive, via elements of a kinematic chain, z. As gear, trigger, and / or a shift rod, an electrical switching of the vacuum interrupter 2 drive, in particular by moving a movable contact piece in the vacuum interrupter 2 on a fixed contact piece and / or away. The high voltage circuit breaker 1 can be used as a multi-pole switch, in particular as a three-pole switch with three vacuum interrupters 2 , each in an insulator 3 arranged, be formed. Alternatively or additionally, a plurality of vacuum interrupters 2 connected in series and / or in parallel, in an isolator 3 or in different insulators 3 be arranged. An arrangement may be made with insulator columns upright on one or more supports, and / or in T-beam form, each insulator on each side of the T-shape 3 is arranged as an arm of the T-shape.

As previously described, the vacuum interrupter includes 2 a housing in the form of a circular, straight cylinder, which is evacuated inside. The housing is constructed of in particular the same, straight cylindrical ceramic parts, which are joined together via metal parts with transition pieces. The transition pieces are designed in the housing as shielding electrodes or shielding, and mechanically firmly connected to the ceramic parts, in particular by soldering. In the outer area of the vacuum interrupter 2 the transition pieces have a ring shape which serves as shielding rings 4 serve. In the middle area of the vacuum interrupter 2 in which is located inside the vacuum interrupter 2 especially dish-shaped ends of the contacts are located between two shielding rings 4 instead of a ceramic part z. B. arranged a cylindrical metallic shield.

The shielding rings 4 are each in a plane perpendicular to the longitudinal axis 5 the vacuum interrupter 2 on the outer circumference of the vacuum interrupter 2 arranged along the longitudinal axis 5 the vacuum interrupter 2 spaced from each other. The distance between adjacent shielding rings 4 can range from centimeters to meters, especially with shielding rings 4 regularly along the longitudinal axis 5 the vacuum interrupter 2 arranged. In 1 is in a dashed bordered area a section through a shield 4 shown on a page. The cut takes place in a plane in which the longitudinal axis 5 the vacuum interrupter or the axis of rotation 5 the shielding ring 4 lies. In the section has the cross section 6 the shielding ring 4 According to the invention no circular or circular shape, but is parallel to the inner wall 7 of the insulator 3 and parallel to the cylindrical circumference of the vacuum interrupter 2 flattened, ie has a lower to no curvature in the direction of the inner wall 7 of the insulator 3 and in the direction of the cylindrical circumference of the vacuum interrupter 2 on. With in the direction is adjacent to denote.

In the 2 to 4 is the section through the shielding ring 4 , as in the dashed bordered area of 1 shown, enlarged shown. In 2 has the shielding ring 4 in the sectional plane of the rotation axis 5 or the longitudinal axis of the vacuum interrupter 2 and / or the insulator 3 an elliptical shape. In 3 has the shielding ring 4 in the sectional plane of the rotation axis 5 an oval, racetrack-like shape. In 4 has the shielding ring 4 in the sectional plane of the rotation axis 5 a rectangular shape with rounded corners. Due to the shape of the shielding rings 4 Optimum or good shielding of electromagnetic fields is achieved, with a minimum diameter in the direction perpendicular to the axis 5 , This allows for the same distance d the inner wall 7 of the insulator 3 to the shielding rings 4 or to the vacuum interrupter 2 , the inner and outer diameter of the insulator 3 be reduced compared to shielding rings 4 with a circular cross section or with two circular shapes of the section in the plane of the axis 5 ,

The embodiments described above can be combined with each other and / or can be combined with the prior art. So z. B. the transition pieces as a part in the shielding rings 4 be formed as an extra part, z. B. pressed, soldered, welded, and / or glued. Alternatively, the transition pieces each with a shield 4 from one part be made, in particular of a metal sheet, for. B. copper and / or steel sheet. The shielding rings 4 may have the shapes shown in the figures, or other, flattened on the outer and inner circumference of the ring shapes, for. B. on average on each side each hexagonal or polygonal shape with rounded corners. The distance of the shielding rings 4 one another can be regular, in particular with respective shielding rings arranged parallel to each other 4 , Alternatively, z. B. in the central region of the vacuum interrupter 2 a metal cylinder may be arranged instead of ceramic cylinders, wherein the shielding rings 4 in particular can be formed or attached directly to the metal cylinder, and in this area the distance between the shielding rings 4 deviates from the distance of Abschirmringe in the range of interconnected ceramic cylinders. The shielding rings 4 can also be at irregular intervals from one another, in particular along the length of a cylindrical vacuum interrupter 2 be arranged. The vacuum interrupter 2 and / or the shielding rings 4 may include a circular area, ie the base and top surfaces of the vacuum interrupter 2 is circular. Alternatively, the vacuum interrupter 2 and / or the shielding rings 4 another area, z. B. include an elliptical surface.

LIST OF REFERENCE NUMBERS

1

High voltage circuit breaker

2

Vacuum interrupter

3

insulator

4

shielding

5

axis

6

cross-section

7

Inner wall of the insulator

d

Distance of the shield ring ( 4 ) to the inner wall of the insulator ( 3 )

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• EP 0102317 A2 [0004]

Claims (11)

High-voltage circuit breaker (1) with at least one vacuum interrupter (2) which is arranged in an insulator (3) and comprises at least one shielding ring (4), characterized in that the at least one shielding ring (4) is arranged in a sectional plane along an axis of rotation (5). of the Abschirmrings (4) has two of a circular cross section deviating cross sections (6). High voltage circuit breaker (1) after Claim 1 , characterized in that the at least one shield ring (4) in the sectional plane of the rotation axis (5) has two elliptical and / or oval, raceway-like cross sections (6) and / or rectangular cross sections (6) with rounded corners. High-voltage circuit breaker (1) according to any one of the preceding claims, characterized in that the at least one vacuum interrupter (2) is circular cylindrical and the insulator (3) is hollow cylindrical, with a circular base, wherein the at least one vacuum interrupter (2) in the insulator (3) is arranged coaxially. High-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the axis of rotation (5) of the at least one shielding ring (4) is coaxial with the longitudinal axis (5) of the at least one vacuum interrupter (2). High-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the at least one shielding ring (4) is arranged circumferentially around the outer periphery of the at least one vacuum interrupter (2), in particular mechanically stably connected to the at least one vacuum interrupter (2). High-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the cross-sections (6) of the at least one shielding ring (4) in the sectional plane of the axis of rotation (5) of the at least one shielding ring (4) in the direction of the at least one vacuum interrupter (2) and / or flattened in the direction of the inner wall of the insulator (3). High-voltage circuit breaker (1) according to one of the preceding claims, characterized in that two, four or at least six shielding rings (4) are included. High-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the at least one shielding ring (4) is mechanically and / or electrically connected to at least one shielding electrode in the interior of the at least one vacuum interrupter (2). High-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the at least one shielding ring (4) made of a conductive material, in particular a metal, in particular copper and / or steel, or a conductive plastic, or plastic with conductive particles, in particular silicone with soot particles is formed. High-voltage circuit breaker (1) according to one of the preceding claims, characterized in that the at least one shielding ring (4) has a minimum and / or maximum distance (d) to the inner wall of the insulator (3) in the range of millimeters to a few centimeters. Method for electromagnetic shielding of at least one vacuum interrupter (2) in an insulator (3) of a high voltage circuit breaker (1), in particular in a high voltage circuit breaker (1) according to one of the preceding claims, with electromagnetic shielding of the at least one vacuum interrupter (2) by at least one shielding ring (4), whose two cross-sections (6) in the sectional plane of the rotation axis (5) adjacent to the at least one vacuum interrupter (2) and / or adjacent to the insulator (3) flattened compared with the cross section in the direction parallel to the axis of rotation (5).

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